The present invention relates to a production management system a production management apparatus and a production management method for managing a production state of a manufacturing line.
Conventionally, at a manufacturing line, products are produced by controlling various devices disposed on a manufacturing line with a programmable logic controller (PLC) or a personal computer. A PLC is basically configured with a calculation unit, an input unit and an output unit. Detection information indicating operating states of various devices is input from a detection device via the input unit, and the operating states of various devices are determined based on the detection information by the calculation unit. Then, a control instruction for allowing each of various devices to execute the determined operating state is output to an actuator of each of various devices via the output unit.
However, a conventional PLC that is exclusively intended to operate a manufacturing line without causing abnormality, to detect abnormality occurring in various devices, to prevent occurrence of abnormal operation in various devices, and/or to indicate current operating states of various devices is not suitable for managing a production state of an entire manufacturing line nor for managing a production efficiency of the manufacturing line. That is, a PLC is a device programmed according to each device to be controlled so as to be provided in each device, not being a device for controlling an entire manufacturing line. Therefore, in some cases, the detection information input in each PLC is not suitable to be used in management of a manufacturing line. In addition, aggregation of the detection information from each PLC requires a communication unit for communication with an external device, for example, a server, and each PLC has a unique communication protocol. Furthermore, each PLC is configured in one unit including a calculation unit, an input unit and an output unit, which is expensive.
Some manufacturing lines do not have a PLC or a personal computer. It is not realistic to newly introduce a PLC to such a manufacturing line, in order to manage the production state and the production efficiency thereof.
Therefore, it is desired to manage the production state and the production efficiency in a manufacturing line by a simple apparatus.
The present invention provided so as to solve at least a part of the above-described problems is to manage the production state and the production efficiency of a manufacturing line by a simple apparatus.